The foundation of all grade control programmes should be that of geological understanding led by clear and accurate mapping and representative sampling to drive appropriate estimation strategies and mining. Gold veins show features relating to erratic grade distribution (nugget effect), and variable geometry and internal architecture.
A high-grade deposit could have gold values ranging from 10 to more than 150 grams per tonne, whereas a low-grade deposit grades in the range of 1 to 5 grams. Low-grade deposits may have up to, and possibly more than, 200 million tonnes of rock, whereas a high-grade deposit is frequently smaller.
Aug 18, 2014· Effective domain selection for grade control in narrow vein gold deposits, in Proceedings Ninth International Mining Geology Conference 2014,pp 191–196 (The Australasian Institute of Mining and Metallurgy: Melbourne). Full Article Download: (6614 kb) OneMine, Inc. [email protected] +1 303 948 4248 Fax
Grade control strategy is intimately linked to mine size and mining method. Vein systems typically contain both barren and productive segments with gold grade varying laterally,
Grade-control activities provide an important framework in which to develop geological understanding of the deposit: the critical feature of narrow gold veins is their strong geological controls.
The confident determination of the structural timing of veins in deposits is critical but challenging, and is at the center of divergences of interpretation of the origin of many greenstone gold deposits. A number of guidelines are offered to help distinguish pre-orogenic veins and deposits from those with syn- to postorogenic timing.
The foundation of all grade control programmes should be that of geological understanding led by clear and accurate mapping and representative sampling to drive appropriate estimation strategies and mining. Gold veins show features relating to erratic grade distribution (nugget effect), and variable geometry and internal architecture.
Grade control geological mapping in underground gold vein operations S. C. Dominy*1,2,3 and I. M. Platten4 Grade control is a process of maximising value and reducing risk. It requires the delivery of
knowledge, the mining process can be more efficient and cost effective. This paper reviews the issues of grade control in underground gold mines and focuses on integrated mapping and sampling through three case studies. FORMAL CITATION: Dominy, S C, Platten, I M, Fraser, R M, Dahl, O and Collier, J B, 2009. Grade control in underground gold
Robert, F., Poulsen, K.H., and Dubé, B. G OLD DEPOSITS AND THEIR GEOLOGICAL CLASSIFICATION 211 Table 1: Commonly recognized types of lode gold deposits and their main geological attributes (cont’d.) Deposit Type Associated Alteration Metal Association Size & Grade of Deposits Selected References
OTHER EXPLORATION GUIDES: Strong structural control on veins and common occurrence of deposits in clusters can be used to locate new veins. ECONOMIC FACTORS TYPICAL GRADE AND TONNAGE : Individual vein systems range from several hundred to several million tonnes grading from 5 to 1500 g/t Ag, 0.5 to 20% Pb and 0.5 to 8% Zn.
The confident determination of the structural timing of veins in deposits is critical but challenging, and is at the center of divergences of interpretation of the origin of many greenstone gold deposits. A number of guidelines are offered to help distinguish pre-orogenic veins and deposits from those with syn- to postorogenic timing.
Oct 17, 2019· Epithermal gold deposits are among the richest gold deposits in the world with some bonanza grade ore shoots containing more than 1000 g/t gold, or in other words, a kilogram of gold for every tonne of rock mined. Unfortunately, the tonnage of ore in epithermal veins is typically small compared with other types of lower grade gold deposits. Gold mineralisation within epithermal veins
Dec 23, 2018· There are many more low-grade gold deposits than high-grade. For every 2.5 grams per tonne (g/t) gold deposit, Mother Nature forms another 10 deposits around 1 g/t.
Gold deposits are found in a variety of geological conditions, identifying these indicators of gold geology will increase your likelihood of finding gold.
Oct 17, 2019· This type of low-grade metamorphism results in collection of minerals which are mostly green, including chlorite, muscovite, albite and epidote, hence the name greenstone. Ore formation Gold and quartz from hydrothermal vein through a greenstone from the
the processes that control gold endowment of an orogenic terrane is to compare the nature of shear systems that are richly endowed with those that are not. The approximately 80-km-long Bardoc Tectonic Zone (BTZ, Fig. 1) is one such shear system that only hosts small deposits. It produced ∼100 tonnes of gold from more than 80 recent
Deposit form and geometry can vary greatly but, in many cases, these features also reflect the nature of the ore-forming process. Thus, hydrothermal deposits show forms related to the geometry of the fluid channelways (e.g., veins or stockworks along fractures). Syngenetic deposits are commonly stratabound (i.e., confined to a particular
Bonanza gold grade epithermal quartz gold-silver style mineralization comprising gold fill of an open quartz vein, Edie Creek. An extremely efficient mechanism of gold deposition is required to remove gold from solution and form bonanza grade gold deposits.
The Dufferin deposit is orogenic, turbidite hosted quartz–carbonate vein deposit. Most of the gold is from narrow, high-grade veins in relatively shallow (300 metre) underground mines.The more significant gold deposits in the Meguma Terrane are located in the Goldenville Formation, in and adjacent to quartz veins.